Range- Range is the difference
between the largest and smallest data points.
Percentile- A method to rank data. If you
are in the 90th percentile, that means that you scored better
than 90% of all the people but not as well as the other 10%
Quartile- Quartiles are values that divide a sample
of data into four groups containing (as far as possible) equal
numbers of observations. A data set has three quartiles. References
to quartiles often relate to just the outer two, the upper
and the lower quartiles; the second quartile is the median.
The lower quartile is the data value a quarter way up through
the ordered data set (25th percentile); the upper quartile
is the data value a quarter way down through the ordered data
set (75th percentile).
Interquartile Range- This is the difference of Q1
and Q3, which accounts for 50% of the data.
5-Number Summary- A 5-number summary is
especially useful when we have so many data that it is sufficient
to present a summary of the data rather than the whole data
set. It consists of 5 values: the most extreme values in the
data set (maximum and minimum values), the lower and upper
quartiles, and the median. A 5-number summary can be represented
in a diagram known as a box and whisker plot. In cases where
we have more than one data set to analyze, a 5-number summary
is constructed for each, with corresponding multiple box and
Mean Absolute Deviation- This is the arithmetic average
deviation (without regard to plus or minus) of a value from
the mean of a set of values.
Transformations- This is the method to change data
depending on the units of measure or other changes.
Standard Deviation- This is a measure of variation
equal to the square root of the mean of the squares of the
deviations from the arithmetic mean of distribution.